Philosophical transactions of the Royal Society of London. Series B, Biological sciences
December 5, 2012
Emma Puighermanal, Arnau Busquets-García, Rafaël Maldonado et al.
Exogenous cannabinoids, such as delta9-tetrahydrocannabinol (THC), as well as the modulation of endogenous cannabinoids, affect cognitive function through the activation of cannabinoid receptors. Indeed, these compounds modulate a number of signalling pathways critically implicated in the deleterious effect of cannabinoids on learning and memory. Thus, the involvement of the mammalian target of...
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
July 23, 2012
Ronald S. Duman, Nanxin Li
361 citations
Molecular and cellular studies have demonstrated opposing actions of stress and antidepressant treatment on the expression of neurotrophic factors, particularly brain-derived neurotrophic factor, in limbic structures of the brain. These changes in neurotrophic factor expression and function result in structural alterations, including regulation of neurogenesis, dendrite length and spine density...
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
May 1, 2012
David Rosenthal
Conscious mental states are states we are in some way aware of. I compare higher-order theories of consciousness, which explain consciousness by appeal to such higher-order awareness (HOA), and first-order theories, which do not, and I argue that higher-order theories have substantial explanatory advantages. The higher-order nature of our awareness of our conscious states suggests an analogy...
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
May 1, 2012
Stephen M Fleming, Raymond J Dolan, Christopher D Frith
Many complex systems maintain a self-referential check and balance. In animals, such reflective monitoring and control processes have been grouped under the rubric of metacognition. In this introductory article to a Theme Issue on metacognition, we review recent and rapidly progressing developments from neuroscience, cognitive psychology, computer science and philosophy of mind. While each of...
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
May 1, 2012
Bert Timmermans, Leonhard Schilbach, Antoine Pasquali et al.
Metacognition is usually construed as a conscious, intentional process whereby people reflect upon their own mental activity. Here, we instead suggest that metacognition is but an instance of a larger class of representational re-description processes that we assume occur unconsciously and automatically. From this perspective, the brain continuously and unconsciously learns to anticipate the...
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
May 1, 2012
Morten Overgaard, Kristian Sandberg
In experimental investigations of consciousness, participants are asked to reflect upon their own experiences by issuing reports about them in different ways. For this reason, a participant needs some access to the content of her own conscious experience in order to report. In such experiments, the reports typically consist of some variety of ratings of confidence or direct descriptions of...
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
November 12, 2008
Michael A. Wheeler, Andy Clark
Much recent work stresses the role of embodiment and action in thought and reason, and celebrates the power of transmitted cultural and environmental structures to transform the problem-solving activity required of individual brains. By apparent contrast, much work in evolutionary psychology has stressed the selective fit of the biological brain to an ancestral environment of evolutionary...
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
June 1, 2008
Lambros Malafouris
This paper presents the possible outline of a framework that will enable the incorporation of material culture into the study of the human self. To this end, I introduce the notions of extended self and tectonoetic awareness. Focusing on the complex interactions between brains, bodies and things and drawing a number of different and usually unconnected threads of evidence from archaeology,...
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
June 1, 2008
Colin Renfrew
The human genome, and hence the human brain at birth, may not have changed greatly over the past 60000 years. Yet many of the major behavioural changes that we associate with most human societies are very much more recent, some appearing with the sedentary revolution of some 10000 years ago. Among these are activities implying the emergence of powerful concepts of value and of the sacred. What...
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
May 29, 2007
Sid Kouider, Stanislas Dehaene
Understanding the extent and limits of non-conscious processing is an important step on the road to a thorough understanding of the cognitive and cerebral correlates of conscious perception. In this article, we present a critical review of research on subliminal perception during masking and other related experimental conditions. Although initially controversial, the possibility that a broad...
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
May 1, 2007
Geraint Rees
The immediacy and directness of our subjective visual experience belies the complexity of the neural mechanisms involved, which remain incompletely understood. This review focuses on how the subjective contents of human visual awareness are encoded in neural activity. Empirical evidence to date suggests that no single brain area is both necessary and sufficient for consciousness. Instead,...
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
April 1, 2007
Nicholas Humphrey
Human beings are not only the most sociable animals on Earth, but also the only animals that have to ponder the separateness that comes with having a conscious self. The philosophical problem of 'other minds' nags away at people's sense of who--and why--they are. But the privacy of consciousness has an evolutionary history--and maybe even an evolutionary function. While recognizing the...
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
December 1, 2006
Jean-Pierre Changeux
The question is raised of the relevance of experimental work with the mouse and some of its genetically modified individuals in the study of consciousness. Even if this species does not go far beyond the level of 'minimal consciousness', it may be a useful animal model to examine the elementary building blocks of consciousness using the methods of molecular biology jointly with investigations...
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
June 1, 2005
Francis C. Crick, Christof Koch
The claustrum is a thin, irregular, sheet-like neuronal structure hidden beneath the inner surface of the neocortex in the general region of the insula. Its function is enigmatic. Its anatomy is quite remarkable in that it receives input from almost all regions of cortex and projects back to almost all regions of cortex. We here briefly summarize what is known about the claustrum, speculate on...
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
June 1, 2005
Jeffrey M Schwartz, Henry P. Stapp, Mario Beauregard
Neuropsychological research on the neural basis of behaviour generally posits that brain mechanisms will ultimately suffice to explain all psychologically described phenomena. This assumption stems from the idea that the brain is made up entirely of material particles and fields, and that all causal mechanisms relevant to neuroscience can therefore be formulated solely in terms of properties of...
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
February 1, 2003
Ami Klin, Warren Jones, Robert Schultz et al.
881 citations
Normative-IQ individuals with autism are capable of solving explicit social cognitive problems at a level that is not matched by their ability to meet the demands of everyday social situations. The magnitude of this discrepancy is now being documented through newer techniques such as eye tracking, which allows us to see and measure how individuals with autism search for meaning when presented...
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
March 1, 2001
Paul C. Bressloff, Jack D. Cowan, Martin Golubitsky et al.
This paper is concerned with a striking visual experience: that of seeing geometric visual hallucinations. Hallucinatory images were classified by Klüver into four groups called form constants comprising (i) gratings, lattices, fretworks, filigrees, honeycombs and chequer-boards, (ii) cobwebs, (iii) tunnels, funnels, alleys, cones and vessels, and (iv) spirals. This paper describes a...
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
November 29, 1998
M. E. Raichle
130 citations
This paper presents a functional brain-imaging strategy designed to isolate neural correlates of consciousness in humans. This strategy is based on skill learning. In the example presented (rapidly generating verbs for visually presented nouns), a cognitive skill is examined before and after practice. As shown, there are marked qualitative differences in the neural circuitry supporting...
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
November 1, 1998
J R Searle
The neurosciences have advanced to the point that we can now treat consciousness as a scientific problem like any other. The problem is to explain how brain processes cause consciousness and how consciousness is realized in the brain. Progress is impeded by a number of philosophical mistakes, and the aim of this paper is to remove nine of those mistakes: (i) consciousness cannot be defined;...
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
November 1, 1998
V S Ramachandran
Words such as 'consciousness' and 'self' actually encompass a number of distinct phenomena that are loosely lumped together. The study of neurological syndromes allows us to explore the neural mechanisms that might underlie different aspects of self, such as body image and emotional responses to sensory stimuli, and perhaps even laughter and humour. Mapping the 'functional logic' of the many...
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
November 1, 1998
Consciousness and the structure of neuronal representations.
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
August 1, 1997
R L Gregory
Following Hermann von Helmholtz, who described visual perceptions as unconscious inferences from sensory data and knowledge derived from the past, perceptions are regarded as similar to predictive hypotheses of science, but are psychologically projected into external space and accepted as our most immediate reality. There are increasing discrepancies between perceptions and conceptions with...
Philosophical transactions of the Royal Society of London. Series B, Biological sciences
October 29, 1996
C Frith
Many patients with schizophrenia report hallucinations in which they hear voices talking to them or about them. Behavioural and physiological studies show that this experience is associated with processes occurring in auditory language systems associated with both the production and the reception of speech. I propose that hallucinations are experienced because patients have difficulty in...